1. Field of the Invention
The present invention relates to a video camera having a storage medium-equipped recorder-reproducer and a control method for controlling the camera. More particularly, the invention relates to a video camera having a storage medium-equipped recorder-reproducer and a control method thereof, the camera having fewer components costing less than comparable conventional models.
2. Description of the Related Art
FIG. 3 is a block diagram of a conventional portable video camera having a video cassette recorder. The video cassette recorder-equipped video camera of FIG. 3 is constituted primarily by a video camera 31 and a video cassette recorder 32. The video camera 31 includes a CCD 11 for picking up images of objects, and a camera signal processing circuit 12 for processing the output of the CCD 11 and outputting a video signal illustratively in the NTSC format. The video camera 31 comprises a synchronizing signal generation circuit 13 made up of a vertical synchronizing signal generation circuit 14 and a horizontal synchronizing signal generation circuit 15. A vertical synchronizing signal (signal CAM VD) and a horizontal synchronizing signal (signal CAM HD) generated respectively by the vertical and horizontal synchronizing signal generation circuits 14 and 15 are supplied to the camera signal processing circuit 12.
The video cassette recorder 32 comprises a cassette tape drive unit 19 that records on a video cassette 19A the video signal coming from the video camera 31 and reproduces the video signal from the video cassette 19A. The video signal (PB RF) reproduced and output by the cassette tape drive unit 19 is fed to a synchronization separation circuit 18 via a contact PB of a switch 17 in a video IC 16. Via another contact EE of the switch 17, the synchronization separation circuit 18 receives the video signal (CAM Y) output by the camera signal processing circuit 12.
The switch 17 is designed to select a video signal either through the contact PB (signal PB RF) or the contact EE (signal CAM Y) and to output the selected signal as a line-out signal to the cassette tape drive unit 19 and an external device. The line-out signal is also supplied to an LCD panel device 2 via an adder 27 and a terminal 28.
The synchronization separation circuit 18 separates a composite synchronizing signal from the video signal received via the switch 17, and forwards the separated composite signal to a horizontal synchronization separation circuit 29 and a vertical synchronization separation circuit 21. The horizontal synchronization separation circuit 29 separates a horizontal synchronizing signal from the received composite synchronizing signal and feeds the separated signal to a PLL circuit (AFC circuit) 30. The PLL circuit 30 generates a reproduced horizontal synchronizing signal in synchronism with the received horizontal synchronizing signal, and outputs the signal thus generated to an OSD IC 26 via the contact PB of the switch 25.
The vertical synchronization separation circuit 21 in a mechanism control microcomputer 20 separates a vertical horizontal synchronizing signal from the received composite synchronizing signal and supplies the separated signal to a horizontal synchronizing signal generation circuit 23 via a contact PB of a switch 22. In addition, the vertical synchronizing signal generation circuit 23 receives via a contact EE of the switch 22 the vertical synchronizing signal output by the vertical synchronizing signal generation circuit 14. The vertical synchronizing signal (signal PBV) generation circuit 23 generates a reproduced vertical synchronizing signal in synchronism with the vertical synchronizing signal received through the switch 22, and forwards the generated signal to the OSD IC 26.
The OSD IC 26 generates pulses representing characters and figures to be inserted onto a screen in synchronism with the reproduced horizontal and vertical synchronizing signals received above (the pulses are called on-screen display (OSD) pulses). The generated pulses are sent to the adder 27.
The adder 27 overlays the video signal from the video IC 16 with the OSD pulses from the OSD IC 26. The result of the overlay operation is output to the LCD panel device 2 via the terminal 28.
An operation unit 24 is operated by a user wishing to manipulate the video camera 31 or video cassette recorder 32 as desired. Signals representing the desired operations are output to the mechanism control microcomputer 20.
The above-described circuits and components are all incorporated in a camcorder enclosure 1.
The LCD panel device 2 is attached as a single component to the camcorder enclosure 1. The LCD panel device 2 accommodates an LCD panel 46 that displays the video signal received through the terminal 28. A synchronizing signal separation circuit 41 in the LCD panel device 2 separates the composite synchronizing signal from the video signal received via the terminal 28, and sends the separated signal to a horizontal synchronization separation circuit 42 and a vertical synchronization separation circuit 44 in an LCD controller 47. The horizontal synchronization separation circuit 42 separates a horizontal synchronizing signal from the received composite synchronizing signal, and outputs the separated signal to a PLL circuit (AFC circuit) 43. The PLL circuit 43 generates a reproduced horizontal synchronizing signal in synchronism with the horizontal synchronizing signal received from the horizontal synchronization separation circuit 42, and forwards the generated signal to the LCD panel 46. The vertical synchronization separation circuit 44 separates a vertical synchronization signal from the received composite synchronizing signal, and sends the separated signal to a gate driver 45. The gate driver 45 generates gate driver start pulses in phase with the received vertical synchronizing signal, and outputs the generated pulses to the LCD panel 46.
In the example above, the user first operates the operation unit 24 to order the mechanism control microcomputer 20 to make the video camera 31 pick up images. In turn, a video signal representing an object picked up by the CCD 11 of the video camera 31 is fed to the LCD panel 46 for display. Characters and symbols denoting the operations performed on the operation unit 24 are generated by the OSD IC 26 and overlaid onto the video signal by the adder 27. The overlay operation allows the LCD panel 46 to display the characters and figures generated by the OSD IC 26.
The operation unit 24 may be operated to establish a recording mode. In this mode, part of the video signal fed to the LCD panel 46 is forwarded to the cassette tape drive unit 19 and recorded onto the video cassette 19A.
When the operation unit 24 is operated to order signal reproduction from the video cassette 19A, a reproduced signal from the cassette tape drive unit 19 is output to the LCD panel 46 for display. At this point, too, OSD signals generated by the OSD IC 26 are suitably output to and displayed on the LCD panel 46.
Where recordings of the video cassette 19A are reproduced in the above example, the horizontal synchronization separation circuit 29 and PLL circuit 30 generate and output a reproduced horizontal synchronizing signal needed to generate the OSD signals. The horizontal synchronization separation circuit 42 and PLL circuit 43 in the LCD controller 47 generate a reproduced horizontal synchronizing signal necessary for displaying the video signal on the LCD panel 46.
As outlined above, the conventional video cassette recorder-equipped video camera comprises two sets of horizontal synchronization separation circuit and PLL circuit: the horizontal synchronization separation circuit 29 and PLL circuit 30 for generating a reproduced horizontal synchronizing signal fed to the OSD IC 26 on the one hand, and the horizontal synchronization separation circuit 42 and PLL circuit 43 in the LCD controller 47 for generating a reproduced horizontal synchronizing signal supplied to the LCD panel 46 on the other hand. An obvious disadvantage of such a redundant circuit constitution is an increased number of components resulting in higher costs.